The Property is located at the northern extent of the southern Peru Au-Ag epithermal belt. Mineralisation identified at the Property is of a high-sulphidation (HS) epithermal type hosted in volcanic rocks close to the Chonta fault, a regionally significant NNW trending structure. The Chonta fault is a major geological break which separates Cenozoic volcanic deposits from folded Paleozoic sediments. Zoned alteration and mineralisation are centred on dacitic and rhyodacitic domes intruded close to the Chonta Fault at its intersection with subordinate NE faults.

Outcrop is obscured by vegetation and quaternary deposits.

The north-northwest trending Chonta fault, obscured in part by quaternary deposits, separates folded Cretaceous and Jurassic sediments from Cenozoic volcanics and is the main conduit for extensive hydrothermal alteration.

Hydrothermal alteration related to inferred buried intrusions is recorded to the southwest of the Chonta fault in Cenozoic volcanics. Centres of alteration, observable on remote sensingimagery, are mapped along the Chonta fault. Alteration is particularly strong where secondary northeast faults intersect the Chonta fault.

Variably sub-cropping and outcropping dacite and rhyodacite domes and more recent volcanic deposits dominate geology and the Property. Domes broadly define the margins of a collapsed caldera structure measuring 4.5 by 3.5 km, elongate along a north-northwest trend (Coffey, 2010).

The NNW Andean trend is well developed and is the dominant orientation of faulting and fold hinges at the Property. The hydrothermal system which drove alteration and mineralisation at the Property is focused along the Chonta fault. Intense alteration, brecciation and mineralisation are intimately associated with the Chonta fault, specifically where it is crosscut by east-west and northeast tensional structures.

Zoned alteration, typical of a high-sulphidation (HS) epithermal system, is recognised at the property. Zones of vuggy silica occur within a more widely developed silica and alunite alteration assemblage. These zones of alteration grade into more expansive argillic alteration and localised but distal zones of propylitic alteration. Vuggy silica centres approximately align along the NNW Andean trend.

Zones of increased grade are typically associated with vuggy silica in the near surface oxidation zone. Interpretation of drilling data indicates that oxidation extends some 80 m below the surface.

Gold mineralization at Corihuarmi is mined by open pit methods. In 2020, the average grade produced was 0.25 grams per tonne (“g/t”) gold, with 22,593 ounces of gold recovered through a leaching process.

Mining at Corihuarmi uses a conventional truck and excavator configuration. Open pits are mined on 5 meterhigh benches through drilling, blasting, loading and hauling unit operations. The material transportation circuit is performed in two parts. First is from the pit to the crusher, and the second one from the crusher to the leach pad. If the mineralized material does not warrant crushing, the material is transported directly to the leach pad as run-of-mine. The waste is transported to the waste dump.

Crushing
Ore from the mine, with a moisture content of 4 to 5% is transported by trucks to the Run of Mine (ROM) pad. The ore is then either dumped directly into the coarse ore bin (COB) or can be placed on the ROM pad and fed into the COB by front end loader.

Ore is withdrawn from the COB by a vibrating scalping grizzly feeder with 100mm gap size. The plus 100mm is fed into the primary jaw crusher. The minus 100 mm grizzly undersize material and the crusher product both drop onto the jaw crusher discharge conveyor. As the ore travels along the conveyor it is weighed, and lime is added. From this conveyor the ore is discharged onto a stacking conveyor and is stockpiled. The crushed material is reclaimed using a front-end loader and trucks and transported to the heap leach pad.

The Project is a heap leach operation utilizing a multiple-lift, single-use leach pad. Prior to placing the ore onto the leach pad the ore is primary crushed. Processing of ore began in January 2008 when irrigation of the heaps was started.

Heap Leaching
Heap Leaching is carried out in a single stage system. Pregnant Leach Solution (PLS) is delivered to activated carbon contactors to remove the gold after which the solution is pumped back to the heap leach pad. The activated carbon in the contactors is stripped from the carbon in a Zadra elution plant and the gold is electrowon onto cathodes. Sludge is removed from the cathodes and retorted to recover mercury prior to being direct smelted to recover the gold into bullion ready for sale.

The current heap leach pad covers an area of nine hectares and is designed to treat 6000tpd. Trucks enter the leach pad via a ramp at one end and dump the ore within one to two metres from the edge of the heap. A bulldozer i ........